PDBsum entry: 2vyo

Hydrolase

PDB id: 2vyo

Contents

Protein chain

206 a.a. *

Ligands

ACT

IMD

EDO

Metals

_CA ×4

_ZN ×2

_CL

Waters ×154

* Residue conservation analysis

PDB id:

2vyo

Name:

Hydrolase

Title:

Chitin deacetylase family member from encephalitozoon cuniculi

Structure:

Chitooligosaccharide deacetylase. Chain: a. Synonym: ecu11_0510. Engineered: yes. Other_details: mature protein. Putative signal peptide removed

Source:

Encephalitozoon cuniculi. Organism_taxid: 284813. Strain: gb-m1. Expressed in: pichia pastoris. Expression_system_taxid: 4922.

Resolution:

1.50Å R-factor: 0.198 R-free: 0.215

Authors:

J.E.Urch,R.Hurtado Guerrero,C.Texier,D.M.F.Van Aalten

Key ref:

J.E.Urch et al. (2009). Structural and functional characterization of a putative polysaccharide deacetylase of the human parasite Encephalitozoon cuniculi. Protein Sci, 18, 1197-1209. PubMed id: 19472335 DOI: 10.1002/pro.128

Date:

25-Jul-08 Release date: 12-Aug-08

Protein chain

Q8SU65  (YB51_ENCCU) -  Polysaccharide deacetylase domain-containing protein ECU11_0510

Seq: 254 a.a.

Struc: 206 a.a.*

* PDB and UniProt seqs differ at 2 residue positions (black crosses)

 Gene Ontology (GO) functional annotation 

• Biological process: carbohydrate metabolic process (1 term)
• Biochemical function: catalytic activity (2 terms)

DOI no: 10.1002/pro.128

Protein Sci 18:1197-1209 (2009)

PubMed id: 19472335

Structural and functional characterization of a putative polysaccharide deacetylase of the human parasite Encephalitozoon cuniculi.

J.E.Urch, R.Hurtado-Guerrero, D.Brosson, Z.Liu, V.G.Eijsink, C.Texier, D.M.van Aalten.

ABSTRACT

The microsporidian Encephalitozoon cuniculi is an intracellular eukaryotic parasite considered to be an emerging opportunistic human pathogen. The infectious stage of this parasite is a unicellular spore that is surrounded by a chitin containing endospore layer and an external proteinaceous exospore. A putative chitin deacetylase (ECU11_0510) localizes to the interface between the plasma membrane and the endospore. Chitin deacetylases are family 4 carbohydrate esterases in the CAZY classification, and several bacterial members of this family are involved in evading lysis by host glycosidases, through partial de-N-acetylation of cell wall peptidoglycan. Similarly, ECU11_0510 could be important for E. cuniculi survival in the host, by protecting the chitin layer from hydrolysis by human chitinases. Here, we describe the biochemical, structural, and glycan binding properties of the protein. Enzymatic analyses showed that the putative deacetylase is unable to deacetylate chitooligosaccharides or crystalline beta-chitin. Furthermore, carbohydrate microarray analysis revealed that the protein bound neither chitooligosaccharides nor any of a wide range of other glycans or chitin. The high resolution crystal structure revealed dramatic rearrangements in the positions of catalytic and substrate binding residues, which explain the loss of deacetylase activity, adding to the unusual structural plasticity observed in other members of this esterase family. Thus, it appears that the ECU11_0510 protein is not a carbohydrate deacetylase and may fulfill an as yet undiscovered role in the E. cuniculi parasite.